1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a multiview image generating method, and more particularly, to a multiview image generating method and a multiview image display apparatus, which are capable of generating a multiview image by generating a hole image and filling a hole area.
2. Description of the Related Art
With the development of electronic technology, various types of electronic appliances have been developed and spread. In particular, display apparatuses such as televisions (TVs), which are one of the home devices which have been most commonly used in households, have been rapidly developed in recent years.
With high performance of the display apparatuses, the kind of contents displayed in the display apparatuses have been also variously increased. In particular, in recent years, a stereoscopic display system which also can be used to watch three-dimensional (3D) contents has been developed and spread.
The stereoscopic display apparatus may be implemented with various kinds of display apparatuses such as 3D TVs used in the households as well as various kinds of monitors, portable phones, personal digital assistants (PDAs), personal computers (PCs), settop PCs, tablet PCs, digital photo frames, kiosks. Further, 3D display technology may be utilized in the households as well as in various fields which require 3D imaging, such as science, medicine, design, education, advertisement, or computer games.
The stereoscopic display system is largely divided into a glasses-free type system which can watch 3D images without glasses and a glasses type system which can watch 3D images with glasses.
There are shutter glasses type display apparatuses as an example of the glasses type system. The shutter glasses type alternately outputs a left-eye image and a right-eye image and alternately opens/closes left and right shutter glasses of 3D glasses worn by a user, which are interlocked with the left and right-images so that the user can feel a 3D effect.
The glasses-free type system is called an autostereoscopy system. The glasses-free type 3D display apparatuses cause light corresponding to different views of images to be projected to a left-eye and a right-eye of the user using a parallax barrier technique or a lenticular lens while displaying a spatially shifted multiview image so that the user can feel a 3D effect.
The glasses type system can provide a satisfactory 3D effect, but there is inconvenience in that the user has to wear the glasses. On the other hand, the glasses-free type system can allow the user to watch 3D images without glasses and thus development of the glasses-free type system has been consistently discussed.
FIG. 1 is a view illustrating a configuration of a glasses-free type 3D display apparatus in the related art. Referring to FIG. 1, the 3D display apparatus in the related art includes a backlight unit 10, an imaging panel 20, and a parallax unit 30.
The parallax unit 30 may include a slit array of an opaque shield which is known as a parallax barrier or a lenticular lens array. FIG. 1 illustrates a case in which the parallax unit 30 is implemented with the lenticular lens array.
As shown in FIG. 1, the imaging panel 20 includes a plurality of pixels divided into a plurality of columns. Images having different points of view for the columns are arranged. In FIG. 1, an example in which a plurality of images 1, 2, 3 and 4 having different points of view are sequentially alternately arranged is illustrated. That is, the pixel columns are arranged as groups indicated with numbers 1, 2, 3, and 4. Graphic signals applied to the panel are arranged so that the pixel column 1 displays a first image and the pixel column 2 displays a second image.
The backlight unit 10 provides light to the imaging panel 20. By the light provided from the backlight unit 10, the images 1, 2, 3, and 4 formed in the imaging panel 20 are projected to the parallax unit 30 and the parallax unit 30 disperses light of the images 1, 2, 3, and 4 projected and transfers the dispersed light toward a viewer. That is, the parallax unit 30 generates exit pupils at a position of the viewer, that is, at a viewing distance. A thickness and diameter of a lenticular lens when the parallax unit 30 is implemented with the lenticular lens array and a space between slits and the like when the parallax unit 30 is implemented with a parallax barrier may be designed so that the exit pupils generated by each column are separated to an average binocular center distance of below 65 mm. The separated image light forms viewing areas, respectively. That is, as shown in FIG. 1, viewing areas 1, 2, 3, and 4 are formed.
In these conditions, when a left-eye 51 of the user is positioned at the viewing area 3 and a right-eye 52 of the user is positioned at the viewing area 2, the user can feel a 3D effect without specific glasses.
The glasses-free system (hereinafter, referred to as a multiview image generating apparatus) generates a plurality of multiview images from an original image. For example, the multiview image generating apparatus may generate images having nine points of view different from each other from one or more original images.
As one example, there may be a method of generating a hole image having a constant point of view from the original image and interpolating a hole area. The multiview image generating method is disclosed in Korean Patent Laid-open Publication No. 20100040593 and 20110085469.
However, the hole area interpolation method in the related art is merely a method of simply filling a hole area with a pixel value of a background adjacent thereto in units of horizontal lines or reducing a size of the hole. In this case, an image of a portion corresponding to a hole area of an actually generated multiview image is often distorted. In particular, when a depth is relatively high like a case in which a background around the hole area is an area structurally protruding in the image, the distortion of the image is serious. Therefore, there is a need for a method of generating a smooth multiview image by effectively processing a portion forming a structure in the original image.